Flash memory is a commonly used type of non-volatile memory in widespread use as mass storage for consumer electronics, such as digital cameras and portable digital music players for example. Such flash memory may take the form of memory cards or USB type memory sticks, each having at least one memory device and a memory controller formed therein. Another mass storage application is solid state drives (SSD), which can be used as replacements for computer hard disk drives. These solid state drives can be used in computer workstations, networks, and for virtually any application in which large amounts of data need to be stored. Cloud computing is an application where user data is stored in a virtual location in the Internet, as opposed to locally in a workstation or other local area network (LAN). It should be appreciated that progressively increasing amounts of mass storage are required as more and more users adopt cloud computing for storing their data.
SSDs are becoming increasingly popular for personal computer and mass storage applications. Unlike traditional hard disk drives with spinning platters and moving magnetic read heads, SSDs have no moving parts. Hence SSDs are tolerant to physical vibrations. SSDs are capable of waking up quickly from a sleep mode in which minimum power is used by all the memory devices within. Traditional hard disk drives, on the other hand, require a relatively longer period of time to wake up from a sleep mode. There may be applications in which such long wake up times are not acceptable, and high speed performance is desired at all times. Therefore, the traditional hard disk drives must remain powered at all times, thereby consuming power even when no data accesses are being executed. Since the traditional hard disk drive is powered all the time, the probability of mechanical failure increases.
The disadvantage of current SSDs is the lower storage capacity for a given hard disk drive form factor. It should be understood that there is currently a 3.5 inch hard disk drive form factor typically used in computer workstations, and a 2.5 inch hard disk drive form factor typically used in laptop computers and other consumer devices where the smaller hard drive size is beneficial. Both form factors are industry adopted standards. Current 2.5 inch traditional hard disk drives can have a storage capacity of 750 GB, while in contrast, currently available 2.5 inch SSDs have a storage capacity of up to 256 GB. Such a storage capacity may not be sufficiently high for users who wish to store their multi-media collections locally. The advent of cloud computing has alleviated the need to store data and multi-media content locally on a computer or laptop. However, this data is typically stored in a data farm housing banks of traditional 3.5 inch hard disk drives. As previously discussed, all drives are kept active since users expect immediate access to their data at any time. As a consequence, significant power is required to keep all the drives running, which results in heating of the drives. Thus, large amounts of power are required to run air conditioners to cool the drives.
Although the 3.5 inch drive form factor is larger than the 2.5 inch drive form factor, the currently used SSD architecture is limited to a practical number of flash memory devices which can be used. While traditional 3.5 inch hard disk drives can be up to 4 TB by example, an SSD version would be limited to about 512 GB. Using lower storage capacity drives in a data farm is not cost effective for the storage space of the data farm.
It is, therefore, desirable to provide a solid-state drive architecture that can provide greater storage capacity for a given form factor or area than prior art solid-state drives currently provide.
It is, therefore, desirable to provide a solid-state drive architecture that can provide greater storage capacity for a given form factor or area than prior art solid-state drives currently provide, and with simplified motherboard design complexity.